Electrically-assisted mechanical braille writer

ABSTRACT

An electrically-assisted mechanical Braille writer includes a main solenoid to apply force to emboss Braille onto a printing medium, and advance an embossing mechanism to the next cell. A second solenoid engages a mechanical stop to prevent one or more embossing keys from being fully depressed, to prevent kickback from the keys mechanically coupling to the main solenoid. In unpowered operation, the mechanical stop is disengaged, and the embossing keys may be fully depressed to apply force to emboss Braille and advance the embossing mechanism. Accordingly, with electrical power, the user may supply a lesser amount of force and still fully emboss Braille cells, while without electrical power, the Braille writer remains fully operational.

RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 13/204,394, entitled “Electrically-Assisted Mechanical BrailleWriter,” filed Aug. 5, 2011; and claims priority to and the benefit ofU.S. Provisional Patent Application No. 61/390,139, titled“Electrically-Assisted Mechanical Braille Writer,” filed Oct. 5, 2010;each of which are hereby incorporated by reference in their entirety.

FIELD OF THE INVENTION

The present disclosure relates to methods and systems for writing andembossing with Braille. In particular, the present disclosure relates toan electrical assist system for a mechanical Braille writer.

BACKGROUND OF THE INVENTION

Braille was invented more than 175 years ago to provide a system thatblind people can use to read and write. Braille is a system of raiseddots that can be read very quickly with the fingers. Braille embossinginvolves pressing one or more pins of a set of blunted embossing pinsarranged in a Braille cell into a printing medium, such as a sheet ofheavy paper, to stretch the printing medium and create a correspondingone or more raised dots. Early manual systems for writing in Brailleincluded a slate with holes arranged in rows of Braille cells and meansfor securing a piece of paper to the slate, and a blunted awl or styluswhich was pressed into the paper to create the raised dot or dots, usingthe holes in the slate as a guide. Later, mechanical impact printers orBraille embossers were created to increase speed and efficiency ofembossing, the first such embosser being the Perkins Brailler,originally manufactured in 1951 by the Perkins School for the Blind,based in Watertown, Mass. Currently, Braille writers exist in eithermechanical or electronic formats. Examples of the former include theBraille Writer manufactured by the Perkins School for the Blind; theTatrapoint and Jot-A-Dot writers manufactured by Quantum Technology ofRydalmere, Australia; the Erika Picht mechanical Braille writermanufactured by Blista-Brailletec gGmbH of Marburg, Germany; and theLavender Braille Writer manufactured by American Printing House for theBlind, Inc. of Louisville, Ky. Examples of electronic Braille writersinclude the Mountbatten from Quantum Technology of Rydalmere, Australia.

Electronic Braille writers may be easy to use, requiring only a lighttouch. However, being based on electric switches and solenoids,electronic Braille writers require constant electrical power to operate.Accordingly, they may suffer from portability issues and may be lessdesirable in developing countries with intermittent or unreliable power.Mechanical Braille writers, on the other hand, may require more force tooperate and be tougher to use, especially for young children.Furthermore, because the solenoids of electronic Braille writers maylock up and the sensors may fail to output signals in the absence ofpower, it may be difficult to combine both mechanical and electronicsystems into a single Braille writer.

SUMMARY OF THE INVENTION

In one aspect, the present disclosure features an electrically-assistedmechanical Braille writer with an automatically-disengaging electricalassist. This mechanism combines the reliability and portability ofmechanical writers with the ease of use of electronic writers. Inunassisted operation, a user presses one or more embossing keys to raisepins of the embosser mechanism to emboss one or more dots of a Braillecell or a space key to advance the carriage, and upon release of thekeys, the embossing mechanism is advanced. The user must press the keysa first predetermined distance, both to emboss the paper and to supplythe energy to advance the embossing mechanism. The user may similarlypress a backspace key, and upon release of the backspace key, theembossing mechanism is advanced backwards.

In assisted operation, the user presses the one or more keys a second,smaller predetermined distance. A mechanical switch, magnetic sensor,optical sensor, or other trigger detects the key press and engages amain solenoid, which lifts the embossing mechanism, supplying the energyfor embossing the paper and advancing the embossing mechanism. Toprevent a kickback from the solenoid from pressing the keys too far, inassisted operation, a second, latching solenoid engages a mechanicalstop that prevents the one or more keys from being pushed to the largerfirst predetermined distance.

Accordingly, with electrical power, the user may supply a lesser amountof force and still fully emboss Braille cells, while without electricalpower, the Braille writer remains fully operational.

In one aspect, the present application is directed to an electricalassist apparatus for a mechanical Braille writer. The electrical assistapparatus includes a first solenoid, attached to an embossing mechanismof a mechanical Braille writer. The electrical assist apparatus alsoincludes a first linkage, attached to the embossing mechanism. Theelectrical assist apparatus further includes a second linkage, attachedto a user-operated lever of the mechanical Braille writer, the secondlinkage oriented to engage the first linkage and offset from the firstlinkage by a first predetermined distance.

In some embodiments, the electrical assist apparatus further comprises aswitch for engaging the first solenoid to emboss a Braille cell, theswitch triggered when the second linkage is moved a second predetermineddistance less than the first predetermined distance. In a furtherembodiment, the switch is triggered via a user-operated lever of themechanical Braille writer being moved to a third predetermined distance.In another further embodiment, the electrical assist apparatus comprisesa mechanical stop for preventing the second linkage from being movedbeyond the second predetermined distance.

In a still further embodiment, the electrical assist apparatus comprisesa second solenoid attached to the mechanical stop, the second solenoidmoving the mechanical stop to a first predetermined position to preventa user-operated lever of the mechanical Braille writer from being movedbeyond a third predetermined distance to cause the second linkage tomove beyond the second predetermined distance. In a still yet furtherembodiment, the electrical assist apparatus comprises a spring attachedto the mechanical stop, the spring moving the mechanical stop to asecond predetermined position in which the user-operated lever is notprevented from moving beyond the third predetermined distance.

In some embodiments, the first solenoid attached to the embossingmechanism further comprises an articulated arm attached to the firstsolenoid and the embossing mechanism. In many embodiments, the secondlinkage comprises one of a sliding lever, hook, catch, ring, and chain.

In another aspect, the present application is directed to a stoppingmechanism for an electrical assist apparatus for a mechanical Braillewriter. The stopping mechanism includes a mechanical stop. The stoppingmechanism also includes a first solenoid attached to the mechanical stopthat, when engaged, moves the mechanical stop to a first predeterminedposition to prevent a user-operated lever of a mechanical Braille writerfrom being moved beyond a first predetermined distance. The stoppingmechanism further includes a spring attached to the mechanical stop, thespring moving the mechanical stop when the first solenoid is disengagedto a second predetermined position in which the user-operated lever isnot prevented from moving beyond the first predetermined distance to asecond predetermined distance.

In some embodiments, the stopping mechanism includes a switch attachedto one of the mechanical stop, the first linkage, the second linkage,and the user-operated lever, the switch triggered to engage a secondsolenoid to cause an embossing mechanism of the mechanical Braillewriter to emboss a Braille cell. In a further embodiment, the switch istriggered when the user-operated lever is moved to the firstpredetermined distance when the first solenoid is engaged. In anotherfurther embodiment, the switch is not triggered when the user operatedlever is moved to the first predetermined distance when the firstsolenoid is not engaged.

In one embodiment, the first solenoid comprises a latching solenoid. Inanother embodiment, the stopping mechanism includes a first linkageconnected to the user-operated lever, and a second linkage, oriented toengage the first linkage and offset from the first linkage by a thirdpredetermined distance. In a further embodiment, the second linkage ismoved to engage the first linkage when the user-operated lever is movedto the second predetermined distance.

The details of various embodiments of the invention are set forth in theaccompanying drawings and the description below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of an embodiment of a mechanical Braillewriter;

FIG. 1B is a perspective, rear view of an embodiment of a mechanicalBraille writer;

FIG. 1C is an exploded, perspective view of an embodiment of amechanical embossing mechanism;

FIG. 1D is a perspective view, with cover removed, of an embodiment of amechanical Braille writer;

FIG. 1E is a top view, with cover removed, of an embodiment of amechanical Braille writer with its cover removed;

FIG. 1F is a bottom view of an embodiment of a mechanical Braillewriter;

FIG. 2A is a perspective cutaway view of an embodiment of a mechanicalBraille writer with an electrical assist mechanism;

FIG. 2B is a magnified view of one embodiment of a linkage as shown inFIG. 2A;

FIG. 2C is a perspective view of one embodiment of a mechanical stop asshown in FIG. 2A;

FIG. 3A is an exploded view of an embodiment of a mechanical Braillewriter with an electrical assist mechanism;

FIG. 3B is a perspective view of an embodiment of a mechanical Braillewriter having an electrical assist mechanism;

FIG. 3C is a block diagram of an embodiment of a control board for amechanical Braille writer having an electrical assist mechanism;

FIG. 4A is a perspective view showing another embodiment of a mechanicalstop element for a mechanical Braille writer including an electricalassist mechanism;

FIG. 4B is a perspective view of the mechanical stop shown in FIG. 4A asinstalled in a mechanical Braille writer having an electrical assistmechanism;

FIG. 4C is another perspective view of the mechanical stop shown in FIG.4A as installed in a mechanical Braille writer having an electricalassist mechanism;

FIGS. 4D and 4E are side views of the mechanical stop shown in FIG. 4A;

FIG. 4F is a perspective view of the mechanical stop shown in FIG. 4Awhen installed in a mechanical Braille writer having an electricalassist mechanism;

FIG. 4G is a side view of the mechanical stop shown in FIG. 4A wheninstalled in a mechanical Braille writer having an electrical assistmechanism;

FIG. 5 is a perspective view of an embodiment of a mechanical Braillewriter having an electrical assist mechanism; and

FIGS. 6A-6B are perspective and back views, respectively, of anembodiment of a mechanical Braille writer with an electrical assistmechanism.

The features and advantages of the present invention will become moreapparent from the detailed description set forth below when taken inconjunction with the drawings, in which like reference charactersidentify corresponding elements throughout. In the drawings, likereference numbers generally indicate identical, functionally similar,and/or structurally similar elements.

DETAILED DESCRIPTION OF THE INVENTION

Illustrated in FIGS. 1A-1F are embodiments of a mechanical Braillewriter 60. As shown in FIG. 1A, in one embodiment, the mechanicalBraille writer 60 includes embossing keys 62, 64, 66, 68, 70, and 72, aspace key 73, a line spacing key 74, and a back space key 76. In someembodiments, the mechanical Braille writer 60 includes margin guides 78and 80 at the front of the Braille writer 60. In other embodiments,margin guides 78 and 80 may be attached to or incorporated within a topcover assembly of the mechanical Braille writer. Thus, although visiblein the embodiments illustrated in FIGS. 1D and 1E, in other embodiments,margin guides 78 and 80 may be removed when a top cover assembly of themechanical Braille writer is removed. In many embodiments, the Braillewriter 60 includes paper advance knobs 82 and 84, which may comprise a“wingnut” configuration for ease of gripping. In some embodiments,Braille writer 60 may also include paper release levers 86 and 88. Inone embodiment, Braille writer 60 may include an embossing mechanism orcarriage assembly 90. In many embodiments, a front portion 91 of theBraille writer 60 may serve as an integrated handle.

Referring now to FIG. 1B, a Braille writer 60 may also include amoveable panel 93, which may serve as an integrated paper tray, readingrest and alignment surface. Moveable panel 93 may, in some embodiments,be rotated or pivoted via a hinge at an upper end of panel 93 to serveas a paper tray, reading rest, or alignment surface. In someembodiments, moveable panel 93 may include a latch, stand, lock, prop,or other mechanism for holding moveable panel 93 in an upright position.Moveable panel 93 may also include a latch for keeping moveable panel 93closed when the Braille writer is carried.

Referring now to FIG. 1C, one embodiment of an embossing mechanism orcarriage assembly 90 includes an array of pins 92 and a guide block orstructure 94. In some embodiments, the array of pins 92 may comprise sixpins, while in other embodiments, other numbers of pins may be provided.For example, in some Braille writing systems, cells may include up toeight dots rather than six. Accordingly, in embodiments of the embossingmechanism for use in these Braille writing systems, there may be eightpins 92. In the embodiment illustrated in FIG. 1C, the pins in the arrayof pins 92 are straight and identical to one another, allowing for easeof assembly and adjustment. The pins may be slidingly guided by guideblock 94. In other embodiments, the pins may be bent, or be bent withstraight portions guided by guide block 94. Each pin 92 may be lifted bya corresponding lifter segment arranged from the front of the Braillewriter to the back and shown below pins 92 in FIG. 1C.

Still referring to FIG. 1C, also shown is a carriage head releasemechanism. A button 100 may be pushed downwardly onto a beam 102. Thebeam 102 then lifts a cell spacer assembly 104 by means of a hooked wire106. Thus, pushing the button 100 results in the lifting of the cellspacer assembly 104 away from the rack bar thereby releasing thecarriage.

In operation, a user may depress one of the embossing keys 62-72,causing a corresponding one of the pins in the array 92 to extend so asto emboss a raised dot on paper (not shown) passing between surfaces ofthe embossing mechanism 90. After a letter is created, the useractivates a spacebar 73 to prepare for embossing a next letter. Inanother embodiment, spacebar 73 may be mechanically linked to embossingkeys 62-72 such that upon release of all depressed embossing keys 62-72,the embossing mechanism 90 is moved to the next Braille cell.

FIGS. 1D, 1E and 1F illustrate cutaway views of embodiments of amechanical Braille writer, showing the mechanical interconnections thatenable embossing. As shown in FIG. 1E, in some embodiments, a Braillewriter 60 may include a paper drum assembly. Referring now to FIG. 1Fwhich shows a cutaway view from below Braille writer 60, embossing keys62-72 are connected via levers to a plurality of bars runninghorizontally across the Braille writer 60. Depressing a key rotates thecorresponding lever, and accordingly raises the corresponding horizontalbar. Each of the plurality of bars correspond to the plurality of liftersegments shown in FIG. 1C, such that lifting the bar raises the liftersegment of the embosser head and the corresponding pin, no matter whereacross a page the embosser head is stationed.

As discussed above, in some embodiments in unassisted operation, a userpresses one or more embossing keys to raise pins of the embossermechanism to emboss one or more dots of a Braille cell or a space key toadvance the carriage, and upon release of the keys, the embossingmechanism is advanced. In these embodiments, the user must press thekeys a first predetermined distance, both to emboss the paper and tosupply the energy to advance the embossing mechanism. The user maysimilarly press a backspace key, and upon release of the backspace key,the embossing mechanism is advanced backwards.

In some embodiments of assisted operation, the user presses the one ormore keys a second, smaller predetermined distance. As used herein,first and second are intended only to illustrate relative terms, and assuch, may be used interchangeably. In one such embodiment, a mechanicalswitch, magnetic sensor, optical sensor, or other trigger detects thekey press and engages a main solenoid, which lifts the embossingmechanism, supplying the energy for embossing the paper and advancingthe embossing mechanism. To prevent a kickback from the solenoid frompressing the keys far enough to significantly depress the rack bar leverto contact the driven embossing mechanism, in some embodiments ofassisted operation, a second, latching solenoid engages a mechanicalstop that prevents the one or more keys from being pushed to the largerfirst predetermined distance. Accordingly, with electrical power, theuser may supply a lesser amount of force and still fully emboss Braillecells, while without electrical power, the Braille writer remains fullyoperational. Different embodiments of the mechanical stop and latchingsolenoid are discussed below in connection with FIGS. 2A-2C and 4A-4F.

Referring now to the embodiment illustrated in FIGS. 2A-2C and first toFIG. 2A, shown is a perspective cutaway view of an embodiment of amechanical Braille writer with an electrical assist mechanism. In briefoverview, a main solenoid 200 is connected via an arm 202 to carriagespacer 204. Carriage spacer 204 is connected via sliding levers 206 aand 206 b to the rack bar lever 302 via rack bar linkages 205 a and 205b. In one embodiment, latching solenoid 208 is placed to move amechanical stop into position when energized.

Still referring to FIG. 2A and in more detail, in some embodiments of aBraille writer in unpowered operation, depressing one or more embossingkeys or the space bar forces the rack bar lever 302 downwards. In someembodiments, rack bar lever 302 may comprise a lever, beam, or otherstructure for translating downward motion of one or more embossing keysand/or space bar into force for embossing a Braille cell by an embossingmechanism. Rack bar lever 302 may further provide a rotational force fora rack bar, discussed in more detail below. In some embodiments, rackbar lever 302 may not provide direct force to emboss the Braille cell,but rather may provide force to rotate or translate an embossingmechanism via a second lever. As shown, in some embodiments, rack barlever 302 may comprise a U-shape with a central portion and two arms.The rack bar lever 302 may be fixed at the end of the two arms, allowingthe central portion to swing as force is applied. In other embodiments,rack bar lever 302 may be attached via springs, hinges, or other means,such that arms are not required. In still other embodiments, rack barlever 302 may be L-shaped, T-shaped, H-shaped, or any other form tocapture downward force from keys and apply the force to a rack bar orother portion of an embossing mechanism.

In some embodiments, rack bar lever 302 pulls, via sliding levers 206a-206 b and rack bar linkages 205 a-205 b, the horizontal bar attachedto carriage spacer 204. In some embodiments, sliding levers 206 a and206 b, referred to generally as sliding lever(s) 206 or firstlinkage(s), may comprise two arms or sides, a pin attaching the two armsto a rack bar lever 302, and a pin or roller, attaching the two arms attheir upper ends. Sliding levers 206 may freely rotate around the lowerpin, and upper roller may allow the levers to apply force to rack barlinkages 205 regardless of angle without slipping.

Rack bar linkages 205 a and 205 b, referred to generally as rack barlinkage(s) 205 or second linkage(s), may comprise L-shaped or T-shapedmetal brackets connects to the horizontal bar attached to carriagespacer 204, with a profile allowing the rack bar linkages to engage orbe engaged by rollers of sliding levers 206. In other embodiments, rackbar linkages 205 may

In other embodiments, sliding levers 206 and rack bar linkages 205 maycomprise matching hooks, a plunger and tube of a pneumatic linkage,chains, a T and eye-ring linkage, or any other type and form of linkagesfor transferring force from rack bar lever 302 to the horizontal barattached to carriage spacer 204. When the rack bar lever 302 is in adefault, non-depressed position, sliding levers 206 and rack barlinkages 205 may be spaced by a first predetermined distance. This firstpredetermined distance may allow the rack bar lever 302 to be depressedto a first predetermined position, less than a second predeterminedposition required for manual or unassisted embossing, without thesliding levers 206 contacting the rack bar linkages 205. In electricalassisted mode, main solenoid 200 may be engaged when the rack bar lever302 is in this first predetermined position, and due to the spacing,vibrations from the solenoid will not be coupled through sliding leversto the rack bar lever, keys, and a user's fingers. In unassisted mode,when the user depresses the keys and rack bar lever to the secondpredetermined position, the sliding levers and linkages may engage,allowing transfer of force from the lever to the embossing mechanism andembossing the Braille cell. For example, in another embodiment usingchains as linkages, the chains may be slack when the keys are at adefault position or to just a first predetermined position, but may betaut and transfer force to the rack bar when the keys are moved beyondthe first predetermined position.

In some embodiments, the bar attached to carriage spacer 204 is held viarotatable pivots at the ends, allowing the bar to slightly rotate.Carriage spacer 204 may be fixed to the bar at a lateral displacementfrom the pivot axis, such that rotating the bar causes carriage spacer204 to swing through an arc rather than merely rotating. In oneembodiment, the teeth of carriage spacer 204 are at separations equal tothe width of a Braille cell, and act as a mechanical escapement for theembossing mechanism, allowing it to advance or retreat precisely oneBraille cell at a time. The spacing may be dependent on the size ofBraille to be embossed.

As discussed above, when powered, in some embodiments, main solenoid 200rotates the horizontal bar attached to carriage spacer 204 directly viaarm 202. Referring briefly to the magnified view of one embodiment of alinkage shown in FIG. 2B, and as discussed above, sliding levers 206 aand 206 b may be pinned at one end to the rack bar lever 302, butslidingly engage hooks, brackets, or rack bar linkages 205 a and 205 battached to the horizontal bar attached to carriage spacer 204. Thus,when main solenoid 200 is engaged, motion of the horizontal arm attachedto carriage spacer 204 does not pull the rack bar lever 302 via levers206 a and 206 b. In other embodiments, as discussed above, variations onlevers 206 a and 206 b may be employed, including hooks, slidingpistons, prismatic joints, catches, or other features such that mainsolenoid 200 and the rack bar lever 302 may both apply pressure tocarriage spacer 204, without main solenoid 200 moving the rack bar lever302.

Returning to FIG. 2A, as discussed above, if a user depresses the rackbar lever 302 too far while in powered operation such that slidinglevers and rack bar linkages are engaged against each other, both mainsolenoid 200 and the rack bar lever 302 via levers 206 a and 206 b maymove carriage spacer 204, and accordingly, vibration from main solenoid200 may be coupled via carriage spacer 204, levers 206 a and 206 b, andthe rack bar lever 302 to the keys and the user's fingers. This maycreate an unpleasant kickback. Accordingly, in some embodiments, asecond solenoid 208 may be employed to engage a mechanical stop toprevent one or more embossing keys from being fully depressed. The rackbar lever 302 may thus be depressed a first predetermined distance, suchas 0.25 inches, while prevented from being depressed far enough to allowsliding levers 206 to engage linkages 205. One such embodiment isillustrated in the perspective view of one embodiment of a mechanicalstop shown in FIG. 2C, while another such embodiment is illustrated inFIGS. 4A-4F.

Referring first to the embodiment illustrated in FIG. 2C, a perspectiveview of one embodiment of a mechanical stop is shown. In one embodiment,second solenoid 208 is connected to travel arm 210, which is connectedat its lower end to the rack bar lever. Second solenoid 208 may comprisea direct current solenoid, alternating current solenoid, or hybridsolenoid. In some embodiments, second solenoid 208 may comprise alatching solenoid.

In some embodiments, travel arm 210 may comprise an arm for pressing atrigger switch when one or more keys are depressed. In some embodiments,travel arm 210 may be moved by second solenoid 208 to engage amechanical stop or bar, preventing further travel by one or more keys.Travel arm 210 may be connected to a bar (not shown) runninghorizontally beneath the one or more keys, such that depressing one ormore keys causes travel arm 210 to move vertically downwards. In oneembodiment, travel arm 210 may slide vertically in a notch of thearmature of latching solenoid 208. In a further embodiment, travel arm210 may include a hole or cut-out portion, and the armature of latchingsolenoid 208 may include a pin, such that the hole and pin comprise aprismatic joint, allowing travel arm 210 to freely move vertically,while being constrained in horizontal motion.

In some embodiments, travel arm 210 may include a bent portion, catch,or other feature, while in other embodiments, travel arm 210 may beattached to a horizontal arm or catch. In these embodiments, such bentportion, arm, catch, or other feature may be positioned to engage amechanical stop 212 when in powered operation. In unpowered operation,latching solenoid 208 may either push travel arm 210 outward pastmechanical stop 212, or pull travel arm 210 inward past mechanical stop212, depending on orientation and type of latching solenoid 208.Conversely, in powered operation, latching solenoid 208 may pull or pushtravel arm 210 such that it engages mechanical stop 212 when one or morekeys are depressed, preventing motion of the keys farther than thepredetermined distance between mechanical stop 212 and the catch, bentportion, or horizontal arm of travel arm 210. Thus, in one embodiment,when unpowered, a user may be able to press one or more embossing keysdown a first predetermined distance, such as 0.75 inches, while whenpowered, the user may only be able to press the one or more embossingkeys down a second, smaller predetermined distance, such as 0.25 inches.

Also shown in FIG. 2C is one embodiment of a trigger switch 214. Triggerswitch 214 may be a mechanical switch, magnetic switch, an electricalswitch employing an electrical contact, an optical sensor, a Hall effectsensor, a capacitive sensor, or any other type and form of switch. Whenin powered operation, trigger switch 214 may control main solenoid 200.In one embodiment, the trigger switch 214 may be engaged by travel arm210. For example, in one such embodiment, trigger switch 214 may be amechanical switch, and when travel arm 210 is positioned by latchingsolenoid 208 for powered operation, trigger switch 214 may be depressedby travel arm 210 or an arm connected to travel arm 210. Because it mayreduce wear on a mechanical switch to refrain from pressing it duringunpowered operation, in another such embodiment, when travel arm 210 ispositioned for unpowered operation by latching solenoid 208, triggerswitch 214 may not be depressed by the travel arm or an arm connected tothe travel arm.

In another embodiment, trigger switch 214 may be a non-mechanicalswitch, such as the magnetic, optical, electric, or other switchesdescribed above. Because mechanical wear may not be an issue with theseswitches, a non-mechanical trigger switch 214 may be positioned suchthat it is triggered both in powered and unpowered operation. In oneembodiment, a non-mechanical trigger switch 214 may be placed as shownin FIG. 2C and detect motion of travel arm 210. In other embodiments, anon-mechanical trigger switch 214 may be placed elsewhere, such as belowthe one or more embossing keys or the space key, or alongside anotherportion of travel arm 210. In yet other embodiments, a plurality oftrigger switches 214 may be employed, such as one for each key, and maybe connected in parallel to control main solenoid 200.

Referring now to FIGS. 3A and 3B, illustrated are exploded andperspective views, respectively, of an embodiment of a mechanicalBraille writer with an electrical assist mechanism. Referring first toFIG. 3A, as discussed above, rack bar lever 302 may be connected tosliding levers 206 a and 206 b, which are placed to respectively engagerack bar linkages 205 a, 205 b attached to carriage spacer 204. Spacekey 73 is attached to space key lever 402, which is fixed at its lowerend to rack bar lever 302, discussed in more detail below. Depression ofspace key 73, in mechanical or unassisted mode, causes space key lever402 to depress rack bar lever 302, as discussed above. Mechanical stopor space bar stop 408 is held out of the way of space key lever 402 viatorsion return spring 422, allowing the space bar to travel the entirestroke distance.

In electrically assisted mode, discussed in more detail below, latchingsolenoid 400, engaged when power is applied, moves mechanical stop 408into position within a U-shaped portion of space key lever 402, belowswitch 404 connected to space key lever 402 (illustrated in more detailand from different angles below). Depression of space key 73, inelectrically assisted mode, moves space key lever 402, causing attachedswitch 404 to contact mechanical stop 408. Switch 404 triggers mainsolenoid 200, as discussed above. Solenoids 200 and 400 and switch 404are connected to control board 300. Control board 300 (also illustratedin the block diagram of FIG. 3C) may comprise a power supply (shown aspower supply 310 in FIG. 3C), transformer, rectifiers, a switch modepower supply, or any other type of power supply. In some embodiments,control board 300, switch 404 and solenoids 200 and 400 may utilizealternating current, while in other embodiments, they may use directcurrent or a mix of direct and alternating current. Control board 300may, in some embodiments, comprise a programmable microprocessor (shownas microprocessor 320 in FIG. 3C) to allow for tuning For example, inone embodiment, control board 300 may comprise a debouncing circuit(shown as debouncing circuit 330 in FIG. 3C) to provide hysteresis tooperation of switch 404, preventing accidental double-triggers of switch404 and solenoid 200. The hysteresis may be programmable, allowingtuning relative to a user's reflexes. This may allow very fast typiststo not be hindered by a long debouncing delay. In some embodiments,control board 300 may provide protection against static discharge, overcurrent, and reverse polarity problems. This may be particularlyvaluable when using the electrical features in areas with questionablepower supplies. In some embodiments, control board 300 may furtherprovide additional features for a Braille writer, including Braillecapture and translation for visual output via a display for sightedteachers or limited-vision users, speech output via a speaker, output toa printer or computer via a serial or parallel connection. Explodedcomponents of FIG. 3A are illustrated in assembled locations in FIG. 3B.

Referring now to FIGS. 4A-4G, illustrated are other embodiments of amechanical stop and trigger for an electrically assisted Braillemechanism. Referring first to FIG. 4A, space key 73 is attached to spacekey lever 402 (shown in transparent view in FIGS. 4A and 4D to show theplacement of mechanical stop 408 and switch 404). Space key lever 402 isshown non-transparently in FIGS. 4B and 4C, for comparison. In someembodiments, space key lever 402 may include the U-shaped upper portionshown and attach to rack bar lever 302 on either side of space key 73,preventing torque-caused rotation when a user depresses space key 73. Inother embodiments, space key lever 402 may be attached in line with thecenter of space key 73 to eliminate torque. Space key lever 402 may thuscomprise a U-shape, T-shape, L-shape, H-shape, I-shape, or any othershape for transferring a downward force from space key 73 to rack barlever 302, and may further contact a switch 404 and mechanical stop 408,when mechanical stop 408 is in a powered or electrical assist modeposition.

As shown in FIG. 4A, latching solenoid 400 is in an energized position,pushing mechanical stop 408 to placement beneath plunger of switch 404.Switch 404 may comprise a SPST switch, a DPST switch, a SPDT switch, aDPDT switch, or any other type of switch. Switch 404 may be a momentaryswitch, leaf switch, capacitive switch, optical switch, magnetic switch,or any other type and form of switch.

In some embodiments, mechanical stop 408 may be attached via a pivot tosolenoid mount 406 as shown. Mechanical stop 408 may rotate around thispivot to extreme positions defined by contact with solenoid mount 406 atupper or lower edges of mechanical stop 408. In other embodiments,solenoid 400 may have a defined throw, such that the mechanical stop 408is prevented from travelling beyond the engaged position shown throughbraking force from solenoid 400. In still other embodiments, a latch orsecond solenoid may lock mechanical stop 408 in an extended positionwhen powered.

Referring briefly to FIG. 4B, latching solenoid 400 and components ofthe mechanical stop 402-408 are illustrated in assembled positionrelative to rack bar lever 302, sliding levers 206, rack bar linkages205 and carriage spacer and embossing elements. In FIG. 4B, keys 62-72and 74-76 and associated levers have been removed for provide clear viewof main solenoid 200 and lever 202, and latching solenoid 400 andmechanical stop components 402-408. Similarly, the chain supportattached to solenoid mount 406 has been removed in FIG. 4B for clarity.For comparison, FIG. 4C includes the chain support attached to solenoidmount 406, illustrating position and attachment of these components inmany embodiments.

Referring now to FIGS. 4D and 4E, and in brief overview, the mechanicalstop and trigger of FIG. 4A are shown in side views. In FIG. 4D, spacekey lever 402 and solenoid mount 406 are illustrated transparently toprovide view of solenoid, switch, and mechanical stop placement. In FIG.4E, space key 73 and space key lever 402 are removed, for comparison.

FIG. 4F illustrates the mechanical stop and trigger of FIG. 4D from aperspective view, with space key 73 and space key lever 402 and keys62-66 similarly removed for clarity. As shown, the mechanical stop maycomprise a U-shape, or may comprise a T-shape, I-shape, O-shape, or anyother shape capable of being moved between a disarmed or manual modeposition, and an engaged or electric assist mode position to preventmotion of space key lever 402 beyond a first predetermined distance.

Referring back to FIG. 4D, and in greater detail, solenoid 400 isattached via T-shaped plunger 420 to mechanical stop 408. Although shownas a T-shaped plunger or armature, in many embodiments, solenoid 400 maybe attached to mechanical stop 408 directly, indirectly, or via one ormore linkages. When solenoid 400 is energized, plunger 420 is extendedand mechanical stop 408 moves to position beneath switch 404 as shown.In some embodiments, mechanical stop 408 pivots around its attachmentpoints to solenoid mount 406, and the lower portion of mechanical stop408 contacts solenoid mount 406 below the pivot, preventing furthertravel. In other embodiments, mechanical stop 408 is prevented fromtraveling further by contact against other components or brakes, or bysolenoid 400 having a fixed throw. When solenoid 400 is not energized,torsion spring 422 returns mechanical stop 408 to a disengaged position,allowing space key 73 and space key lever 402 to be fully depressed tomechanically emboss a Braille cell. In some embodiments, torsion spring422 may return mechanical stop to a position with the top portion ofmechanical stop 408 against or close to solenoid mount 406. In otherembodiments, torsion spring 422 may return mechanical stop to any otherposition that allows full travel of space key lever 402.

Referring now to FIG. 4G, this unassisted or mechanical mode isillustrated, with solenoid mount 406 removed for clarity. As shown,mechanical stop 408 is rotated out of position from within space keylever 402. Depressing the space key 73 in this position will not engageswitch 404 against mechanical stop 408, reducing wear on the mechanicalswitch, as well as allowing space key 73 to fully depress beyond wheremechanical stop would have prevented further travel. Although theembodiments illustrated in FIGS. 4A-4G are shown with a mechanicalswitch 404, in many embodiments, magnetic, optical, or other switchesmay be used, without departing from the scope of the present invention.Although switch 404 is illustrated attached to space key lever 402, insome embodiments, switch 404 may be attached to mechanical stop 408 anddepressed by a portion of space key lever 402. In still otherembodiments, switch 404 may be attached elsewhere, such as on solenoidmount 406, and space key lever 402 may include an extension or arm toengage switch 404 when space key 73 is depressed.

Referring now to FIG. 5, illustrated is a perspective view of anembodiment of a mechanical Braille writer having an electrical assistmechanism. Additional keys and components, including the mechanical stopdiscussed above, have been removed for clarity. As shown, in someembodiments, the rack bar attached to carriage spacer 204, arm 202, andrack bar linkages 205 a and 205 b is attached at its ends to pivots,allowing the carriage spacer 204 to rotate and move through an arc asthe rack bar is rotated, either mechanically via linkages 205 or viamain solenoid 200 and arm 202. Rack bar lever 302 is attached to spacekey lever 402, and sliding levers 206 a and 206 b. Sliding levers 206 aand 206 b may each include a roller at their upper end, forming anattachment point for each of the two halves of the sliding lever,although, as discussed above, different combinations of linkages 205 and206 may be used without departing from the scope of the presentdisclosure. When rack bar lever 302 is depressed in mechanical modebeyond a first predetermined position such that the rollers or linkagesmove beyond a first predetermined distance, the rollers or linkages mayengage rack bar linkages 205 a and 205 b. As shown, in many embodiments,when no keys are depressed, there is a gap between the rollers ofsliding levers 206 a and 206 b and rack bar linkages 205 a and 205 b.This gap allows rack bar lever to be slightly depressed inelectrically-assisted mode, engaging switch 404 against a mechanicalstop as discussed above, without the rollers contacting the linkages.Thus, when main solenoid 200 is engaged, vibration is not coupledthrough the linkages to the sliding levers, rack bar lever, space keylever, and space key to the user's fingers. The rounded profile of rackbar linkages 205 a and 205 b makes up for this gap in mechanical orunassisted mode, catching the rollers of sliding levers 206 a and 206 bas the user presses the keys beyond the distance required forelectrically-assisted mode. As discussed above, in other embodiments,different types and forms of linkages can be employed, wherein force isnot transmitted from the rack bar lever to the rack bar when a userdepresses a key only a first predetermined distance, but force istransmitted when the user depresses the key to at least a secondpredetermined distance, greater than the first predetermined distance.

Referring briefly to FIGS. 6A and 6B, illustrated are perspective andback views, respectively, of an embodiment of a mechanical Braillewriter with an electrical assist mechanism. In some embodiments, a powerswitch 600 may be fixed on the chassis of the writer. Power may beprovided through a port 602, which may be similarly fixed on the chassisof the writer. In the embodiment shown, port 602 may be part of acontrol board or power supply board 300, as discussed above. Asdiscussed above, internal components of the electrical assist mechanismmay automatically position themselves when moving between assisted andunassisted modes. Thus, if power is lost, the Braille writer will stillbe useable. Accordingly, power switch 600 may not be required foroperation or moving to unassisted mode, but may be provided for safetyreasons or for reducing power consumption when not in use.

In some embodiments, the electrical assist and/or mechanical stopsystems discussed above may be provided as add-on or repair kits formodification of an existing mechanical Braille writer. For example,referring back to FIG. 3A, the exploded components may be provided in akit for attaching to or modifying an existing Braille writer.Accordingly, electrical assist capability may be easily added tomechanical Braille writers.

Having described certain embodiments of methods and systems for erasingBraille embossing, it will now become apparent to one of skill in theart that other embodiments incorporating the concepts of the inventionmay be used.

What is claimed:
 1. A stopping mechanism for an electrical assistapparatus for a mechanical Braille writer, comprising: a mechanicalstop; a first solenoid attached to the mechanical stop and, whenengaged, moving the mechanical stop to a first predetermined position toprevent a user-operated lever of a mechanical Braille writer from beingmoved beyond a first predetermined distance; and a spring attached tothe mechanical stop, the spring moving the mechanical stop when thefirst solenoid is disengaged to a second predetermined position in whichthe user-operated lever is not prevented from moving beyond the firstpredetermined distance to a second predetermined distance.
 2. Thestopping mechanism of claim 1, further comprising a switch attached toone of the mechanical stop, the first linkage, the second linkage, andthe user-operated lever, the switch triggered to engage a secondsolenoid to cause an embossing mechanism of the mechanical Braillewriter to emboss a Braille cell.
 3. The stopping mechanism of claim 2,wherein the switch is triggered when the user-operated lever is moved tothe first predetermined distance when the first solenoid is engaged. 4.The stopping mechanism of claim 2, wherein the switch is not triggeredwhen the user operated lever is moved to the first predetermineddistance when the first solenoid is not engaged.
 5. The stoppingmechanism of claim 2, further comprising a debouncing circuit connectedto the switch.
 6. The stopping mechanism of claim 1, wherein the firstsolenoid comprises a latching solenoid.
 7. The stopping mechanism ofclaim 1, further comprising a first linkage connected to theuser-operated lever, and a second linkage, oriented to engage the firstlinkage and offset from the first linkage by a third predetermineddistance.
 8. The stopping mechanism of claim 7, wherein the secondlinkage is moved to engage the first linkage when the user-operatedlever is moved to the second predetermined distance.
 9. The stoppingmechanism of claim 7, wherein the first linkage comprises a roundedprofile and the second linkage comprises a roller.
 10. The stoppingmechanism of claim 1, wherein the user-operated lever of the mechanicalBraille writer is a space key.